Node.js Async vs Await Explained with Real Examples

Master async and await in Node.js with this easy guide. Includes real code examples, pros/cons and practical use cases to make your async code clean and readable.

🔹 Introduction

Handling asynchronous operations in Node.js is a must. Whether it's database access, file I/O or an API call - Node.js uses non-blocking async code.

In this blog, we'll cover:

• What is async and await?

• Why do we use them?

• Real-life examples

• Common mistakes

• Clean-up tips

🔹 What are async and await in Node.js?

async is like saying, This function might take time, like baking a cake, so let's allow it to do its thing without holding up everything else.

await tells the code to hold off and wait until it gets an answer from a promise.

🔹Real Example Without Async/Await

const fetchData = () => {

return new Promise((resolve) => {

setTimeout(() => {

resolve("Data fetched!");

}, 2000);

});

};

fetchData().then((data) => {

console.log(data); // Data fetched!

});

😖 Problem?

Chaining too many .then() statements makes the code ugly and hard to manage.

🔹 Async/Await Version (Clean & Modern)

const fetchData = () => {

return new Promise((resolve) => {

setTimeout(() => {

resolve("Data fetched!");

}, 2000);

});

};

const getData = async () => {

const data = await fetchData();

console.log(data); // Data fetched!

};

getData();

🔹 Use Case: API Call with Fetch

const fetch = require('node-fetch');

const getUser = async () => {

try {

const res = await fetch('https://jsonplaceholder.typicode.com/users/1');

const user = await res.json();

console.log(user.name);

} catch (err) {

console.error('Error:', err.message);

}

};

getUser();

🔹 Common Mistakes

❌ Forgetting await → your variable is a Promise, not the data.

❌ Not using try/catch → unhandled promise rejection.

❌ Mixing then() inside async → defeats the purpose!

🔹 When to Use Async/Await

✅ When you want readable, step-by-step async code

✅ Handling API calls, database queries or file I/O

✅ Replacing long promise chains

🔹 Cleanup Tips

Here's a good pattern using finally():

const doWork = async () => {

try {

// Simulate some asynchronous task, e.g., a network request or a time-consuming operation

const result = await someAsyncFunction(); // 'await' pauses the function until 'someAsyncFunction()' resolves

// After the promise resolves, you can use the result

console.log('Work completed successfully:', result);

} catch (error) {

// If any error occurs during the async operation, it'll be caught here

console.error('An error occurred:', error);

} finally {

// This block will run no matter what, even if there's an error

console.log('Operation completed.');

}

};

Also, in real-world apps, always handle unexpected behavior using:

• process.on('unhandledRejection')

• process.on('uncaughtException')

Using async/await in Node.js makes your asynchronous code cleaner, readable and less error-prone. Ditch the messy .then() chains and make your logic easy to follow.